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	<head>
		<title>three.js WebGL  - postprocessing - FXAA</title>
		<meta charset="UTF-8">
		<meta name="viewport" content="width=device-width, user-scalable=no, minimum-scale=1.0, maximum-scale=1.0">
		<link type="text/css" rel="stylesheet" href="main.css">
		<style>
			body {
				background-color: #fff;
				color: #222;
			}

			a {
				color: #08f;
			}

			#container {
				position: absolute;
				top: 70px;
				width: 100%;
				bottom: 0px;
			}
		</style>
	</head>

	<body>

		<div id="info">
			<a href="https://threejs.org" target="_blank" rel="noopener">three.js</a> - postprocessing - FXAA<br />
			Left: No FXAA, Right: FXAA
		</div>
		<div id="container">
		</div>

		<script type="importmap">
			{
				"imports": {
					"three": "../build/three.module.js",
					"three/addons/": "./jsm/"
				}
			}
		</script>

		<script type="module">

			import * as THREE from 'three';

			import { EffectComposer } from 'three/addons/postprocessing/EffectComposer.js';
			import { RenderPass } from 'three/addons/postprocessing/RenderPass.js';
			import { ShaderPass } from 'three/addons/postprocessing/ShaderPass.js';
			import { OutputPass } from 'three/addons/postprocessing/OutputPass.js';
			import { FXAAShader } from 'three/addons/shaders/FXAAShader.js';

			let camera, scene, renderer, clock, group, container;

			let composer1, composer2, fxaaPass;

			init();

			function init() {

				container = document.getElementById( 'container' );

				camera = new THREE.PerspectiveCamera( 45, container.offsetWidth / container.offsetHeight, 1, 2000 );
				camera.position.z = 500;

				scene = new THREE.Scene();

				clock = new THREE.Clock();

				//

				const hemiLight = new THREE.HemisphereLight( 0xffffff, 0x8d8d8d );
				hemiLight.position.set( 0, 1000, 0 );
				scene.add( hemiLight );

				const dirLight = new THREE.DirectionalLight( 0xffffff, 3 );
				dirLight.position.set( - 3000, 1000, - 1000 );
				scene.add( dirLight );

				//

				group = new THREE.Group();

				const geometry = new THREE.TetrahedronGeometry( 10 );
				const material = new THREE.MeshStandardMaterial( { color: 0xf73232, flatShading: true } );

				for ( let i = 0; i < 100; i ++ ) {

					const mesh = new THREE.Mesh( geometry, material );

					mesh.position.x = Math.random() * 500 - 250;
					mesh.position.y = Math.random() * 500 - 250;
					mesh.position.z = Math.random() * 500 - 250;

					mesh.scale.setScalar( Math.random() * 2 + 1 );

					mesh.rotation.x = Math.random() * Math.PI;
					mesh.rotation.y = Math.random() * Math.PI;
					mesh.rotation.z = Math.random() * Math.PI;

					group.add( mesh );

				}

				scene.add( group );

				//

				renderer = new THREE.WebGLRenderer();
				renderer.setPixelRatio( window.devicePixelRatio );
				renderer.setSize( container.offsetWidth, container.offsetHeight );
				renderer.setAnimationLoop( animate );
				renderer.autoClear = false;
				container.appendChild( renderer.domElement );

				//

				const renderPass = new RenderPass( scene, camera );
				renderPass.clearAlpha = 0;

				//

				fxaaPass = new ShaderPass( FXAAShader );

				const outputPass = new OutputPass();

				composer1 = new EffectComposer( renderer );
				composer1.addPass( renderPass );
				composer1.addPass( outputPass );

				//

				const pixelRatio = renderer.getPixelRatio();

				fxaaPass.material.uniforms[ 'resolution' ].value.x = 1 / ( container.offsetWidth * pixelRatio );
				fxaaPass.material.uniforms[ 'resolution' ].value.y = 1 / ( container.offsetHeight * pixelRatio );

				composer2 = new EffectComposer( renderer );
				composer2.addPass( renderPass );
				composer2.addPass( outputPass );

				// FXAA is engineered to be applied towards the end of engine post processing after conversion to low dynamic range and conversion to the sRGB color space for display.

				composer2.addPass( fxaaPass );

				//

				window.addEventListener( 'resize', onWindowResize );

			}

			function onWindowResize() {

				camera.aspect = container.offsetWidth / container.offsetHeight;
				camera.updateProjectionMatrix();

				renderer.setSize( container.offsetWidth, container.offsetHeight );
				composer1.setSize( container.offsetWidth, container.offsetHeight );
				composer2.setSize( container.offsetWidth, container.offsetHeight );

				const pixelRatio = renderer.getPixelRatio();

				fxaaPass.material.uniforms[ 'resolution' ].value.x = 1 / ( container.offsetWidth * pixelRatio );
				fxaaPass.material.uniforms[ 'resolution' ].value.y = 1 / ( container.offsetHeight * pixelRatio );

			}

			function animate() {

				const halfWidth = container.offsetWidth / 2;

				group.rotation.y += clock.getDelta() * 0.1;

				renderer.setScissorTest( true );

				renderer.setScissor( 0, 0, halfWidth - 1, container.offsetHeight );
				composer1.render();

				renderer.setScissor( halfWidth, 0, halfWidth, container.offsetHeight );
				composer2.render();

				renderer.setScissorTest( false );

			}

		</script>
	</body>
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